Customer background : 

JC Engineering based in India’s Polyester Textile hub Surat is one of the dedicated Yarn Processing machinery manufacturer. They manufacture various kinds of textile machinery Yarn Splitting winder, Precision Cops winders, Cheese winders, TFO etc.

Application details : 

Yarn Splitting Winder (YSW) produces monofilament yarn from multifilament (mother) yarn. This is done by splitting the various filaments of the mother yarn and winding each monofilaments on a different tube while continuously unwinding (pulling) the mother yarn.

Conventional method for Yarn splitting & Its demerits : 

• The mother yarn package being very heavy, required lot of force to unwind, which would reduce as the package got smaller. The unwinding of mother yarn was not assisted by any positive drive force. Since the yarn was directly pulled from the mother yarn package, a lot of tension was introduced on each mono yarn. This resulted in uneven winding tension and lowered the tensile strength of the yarn. Also sensitive yarns could not be processed.
• The application required precise control, so that the yarn is not overfed or under supplied which would result in unstable open loop control resulting in yarn break. No consistent yarn quality obtained.
• Heavy denier yarns at low efficiency (with machine process speed limit up to 350 to 450 MPM) & frequent yarn breaks caused by high tension on yarn.

Summary of disadvantage of conventional control. : 

• Uneven winding tension.
• Sensitive yarns can not be processed.
• Frequent yarn breakage.
• No consistent yarn quality.

Solution Proposed : 

The idea was to provide positive assisted yarn supply to the monofilament winding mechanism at uniform user defined tension so as to over come the above challenges.

Use of VLT in this Application : 

The mother yarn package was directly mounted on the shaft of a motor being controlled by VLT2800 VFD in close loop with a tension sensor placed at intermediate stage to provide adequate feedback to the VLT2800 VFD and user defined set point from embedded PLC. Merits of application with VLT 2800 drive:

• Process all type of yarn from micro to heavy denier. The main cost benefits is by making positive unwinding using VLT it should possible to unwind micro denier like 20 to 50 denier monofilament yarns rather than process only heavy denier monofilament yarns unwinding with conventional machine.
• Increase the process yarn speed & maintain uniform tension through out the process. i.e. 350 MPM to 800MPM.
• Increased productivity & efficiency. Productivity is increased ~100% over conventional method.
• Reduce the no of yarn breakages up to 90 %.
• Achieved excellent closed loop control even at high line speed, while enabling most sensitive yarns to be processed.

The mother yarn package was directly mounted on the shaft of Key Point on this Application development : 

• Excellent control on process due to vector control (VVC+) compare to normal scalar control. This is unique point using VLTs.
• Such unique VFD controlled application m/c is not offered by any other OEM & only 1-2 OEM makes conventional yarn splitter machines.
• Based on this success of this application this OEM choose to work with Danfoss who bought VFDs from other suppliers for Winder applications.

Compelling value proposition for customer to consider Danfoss : 

• Local Application development and technical support by Powertech to develop the application and support by Danfoss Application specialist to prove the load trials.
• VLT2800 performance in VVC+ mode and Built in DC choke, RFI filter features.
• Better EMC compliance and complete system is working on MODBUS RTU give a value addition to end customers in terms of edge over technology.
• Danfoss Brand recognition in Textile market.

Application Developed by:

Danfoss long time business associates Mr. Bhavin & Mr. Vikas of POWERTECH Surat in support with Danfoss application specialist Mr. Gopal Kanani.